Answer:
Scientists believe that comets are the debris left from the solar nebula which condensed to form the Sun and planets in our solar system. Most comets are thought to originate in a huge cloud called the Oort Cloud. ... Comets follow a regular orbit around the Sun.
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Explanation:
Answer:
D. the quantity of heat that is required to raise 1 g of the sample by 1*C (kelvin) at a constant pressure.
Answer:
four elements
Explanation:
He = 1s²
Be = 1s² 2s²
C = 1s² 2s² 2p²
Mg = 1s² 2s² 2p⁶ 3s²
Si = 1s² 2s² 2p⁶ 3s² 3p²
Ca = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
Valence electrons are those electrons which are present in outer most electronic shell.
He, Be, Mg, Ca these four elements have 2 valence electrons.
While Si and C have four valance electrons.
